I am writing from Toronto. I have created some vegetable beds already on my backyard lawn but I always removed the sod layer entirely before putting new soil and compost. Is it OK to cut the sod in flat sheets, including all roots, turn it upside down and leave it in place and later just cover with the new soil and compost? Will that kill the grass or will the grass grow again?
Thank you for contacting the Toronto Master Gardeners. The method you suggest will definitely work. Another method to consider before digging up your sod and turning it over, which will saves lots of time and physical work this year is to use sheet mulching. In either case your old lawn will decompose into wonderful nutritious soil for your vegetables and with the City of Toronto pesticide ban in place, your lawn should be pesticide free.
Sheet mulching involves the layering of cardboard or newspapers followed by the addition of layers of organic matter that will rot down to your existing lawn over the winter, creating a vegetable plot ready for planting in the spring. You will find a note of caution on this method here
All the best for your new vegetable garden!